I did a Server install before which didn't install X Windows so you would just boot into a terminal without all the GUI stuff. If I did a regular Workstation install which installed X Windows, how do I configure it to boot into a terminal without removing X-Windows? I still want the option of using the GUI. Thanks!

If I understand your questions right, you wish to login to the console rather than the GUI. easily done.

You would have to edit /etc/inittab file
Do from a console

vi /etc/inittab

You would see a file, scroll down to the line which reads something like:
id:5:initdefault:

Change the 5 to 3 and your query is answered. Here's how:
1. vi /etc/inittab
2. Press the button 'a' and you will see --INSERT-- at the bottom left.
3. Move the cursor down to the above specified line and change 5 to 3.
4. Press Escape(Esc) key.
5. Press colon( : ) and then write 'wq'
:wq
6.This saves and exits from the file.

Thanks! Is there a command I can type to go back to the GUI once I am logged into the console (text-only)? Or do I have to edit that file again and reboot?

No no. you can run the x server by giving the command

startx

To close down Fedora/Linux and move to command line type telinit 3 then to come back to gui type telinit 5 also when you log into su to enterd this command type "su -" not just "su".

Hope This Helps.